Oracle drop constraint unique and re-add it -

i've drop constraint unique key command:

alter table table     drop constraint unique uk_nome; 

it's removed because don't see it, when try re-add different parameter:

alter table tale add constraint uk_name unique (uk_1, uk_2); 

i receive error:

errore sql: ora-00955: name used existing object.

where problem?

you drop uk_nome , add uk_name. mean there typo in uk_nome.